Common Weakness Enumeration

A Community-Developed List of Software Weakness Types

CWE/SANS Top 25 Most Dangerous Software Errors
Home > CWE List > CWE- Individual Dictionary Definition (3.0)  

CWE-663: Use of a Non-reentrant Function in a Concurrent Context

Weakness ID: 663
Abstraction: Base
Structure: Simple
Status: Draft
Presentation Filter:
+ Description
The software calls a non-reentrant function in a concurrent context in which a competing code sequence (e.g. thread or signal handler) may have an opportunity to call the same function or otherwise influence its state.
+ Relationships

The table(s) below shows the weaknesses and high level categories that are related to this weakness. These relationships are defined as ChildOf, ParentOf, MemberOf and give insight to similar items that may exist at higher and lower levels of abstraction. In addition, relationships such as PeerOf and CanAlsoBe are defined to show similar weaknesses that the user may want to explore.

+ Relevant to the view "Research Concepts" (CWE-1000)
+ Relevant to the view "Development Concepts" (CWE-699)
MemberOfCategoryCategory3617PK - Time and State
ParentOfVariantVariant479Signal Handler Use of a Non-reentrant Function
+ Modes Of Introduction

The different Modes of Introduction provide information about how and when this weakness may be introduced. The Phase identifies a point in the software life cycle at which introduction may occur, while the Note provides a typical scenario related to introduction during the given phase.

Architecture and Design
+ Common Consequences

The table below specifies different individual consequences associated with the weakness. The Scope identifies the application security area that is violated, while the Impact describes the negative technical impact that arises if an adversary succeeds in exploiting this weakness. The Likelihood provides information about how likely the specific consequence is expected to be seen relative to the other consequences in the list. For example, there may be high likelihood that a weakness will be exploited to achieve a certain impact, but a low likelihood that it will be exploited to achieve a different impact.


Technical Impact: Modify Application Data; Read Application Data; Alter Execution Logic

+ Observed Examples
unsafe calls to library functions from signal handler
SIGCHLD signal to FTP server can cause crash under heavy load while executing non-reentrant functions like malloc/free.
+ Potential Mitigations

Phase: Implementation

Use reentrant functions if available.

Phase: Implementation

Add synchronization to your non-reentrant function.

Phase: Implementation

In Java, use the ReentrantLock Class.
+ Memberships
This MemberOf Relationships table shows additional CWE Categories and Views that reference this weakness as a member. This information is often useful in understanding where a weakness fits within the context of external information sources.
MemberOfCategoryCategory986SFP Secondary Cluster: Missing Lock
+ References
[REF-547] SUN. "Java Concurrency API". Class ReentrantLock. <>.
[REF-548] Dipak Jha, Software Engineer, IBM. "Use reentrant functions for safer signal handling". <>.
+ Content History
Modification DateModifierOrganization
2008-07-01Eric DalciCigital
updated References, Potential_Mitigations, Time_of_Introduction
2008-09-08CWE Content TeamMITRE
updated Relationships, References
2009-03-10CWE Content TeamMITRE
updated Related_Attack_Patterns
2010-09-27CWE Content TeamMITRE
updated Name, Observed_Examples, Potential_Mitigations, References, Relationships
2010-12-13CWE Content TeamMITRE
updated Description, Name, Relationships
2011-06-01CWE Content TeamMITRE
updated Common_Consequences
2012-05-11CWE Content TeamMITRE
updated Relationships
2014-07-30CWE Content TeamMITRE
updated Relationships
2017-11-08CWE Content TeamMITRE
updated Observed_Examples
Previous Entry Names
Change DatePrevious Entry Name
2010-09-27Use of a Non-reentrant Function in an Unsynchronized Context
2010-12-13Use of a Non-reentrant Function in a Multithreaded Context

More information is available — Please select a different filter.
Page Last Updated: January 18, 2018